Very pity.Texture atlas not the main idea. Main idea is optimizing memory for textures and HTTP server requests. What is the optimal workflow\advices for organizing textures? (approximately 15-20 textures 32x32 or 256x256)- Power of 2- PNG\JPG - what else?

If textures are simple you can combine 4 textures at one by RGBA layers in png image and then colored them in the node material. Some of textures like lines dots or something else you can recreate using procedural methids. You can find a lot of tutorials on our site and some examples in our SDK search for "procedural lines".